1. Field of the Invention
The invention pertains to radiometric devices for seeking targets against the high background noise temperature of the earth's surface and more particularly relates to radiometric systems adapted to detect special characteristics of targets, even though immersed in such noisy environments, by the processing of received signals representative of those special characteristics and by their recognition by matched-filter processing apparatus.
2. Description of the Prior Art
Radiometric target searching and tracking systems are well known in the art and are generally characterized by several faults making them not totally satisfactory for use in high noise level environments, such as in detecting relatively small metal objects like vehicles in a background of ground clutter. In particular, prior devices employing conventional types of scanning antenna systems generally have a limited field of view so that search of an area of reasonable size requires an unreasonable amount of time. Furthermore, a conventional automatic acquisition system consisting primarily of an envelope detector may have an output wave form caused by the background an order of magnitude greater than the corresponding wave form caused by a target. The conventional envelope detector does not utilize unique features of a target which distinguish it from the background. These and further defects of the prior art remain to be discussed in greater detail.